CHAPTER-7-ORGANIC-MOLECULES

Organic Molecule Overview

  • Organic molecules are essential in microbiology and biochemistry.

Biochemistry and Organic Chemistry

  • Biochemistry: Studies the chemistry of life; explains form and function through chemical principles.

  • Organic Chemistry: Focuses on carbon-based chemistry, foundational for understanding biomolecules and biochemistry.

Most Abundant Elements

  • Macronutrients: Key elements in organic molecules include:

    • Hydrogen (H)

    • Carbon (C)

    • Oxygen (O)

    • Nitrogen (N)

    • Phosphorus (P)

    • Sulfur (S)

Trace Elements

  • Micronutrients: Elements required in smaller amounts:

    • Sodium (Na)

    • Potassium (K)

    • Magnesium (Mg)

    • Zinc (Zn)

    • Iron (Fe)

    • Calcium (Ca)

    • Molybdenum (Mo)

    • Copper (Cu)

    • Cobalt (Co)

    • Manganese (Mn)

    • Vanadium (Va)

Organic vs Inorganic Compounds

  • Organic Molecules: Contain chains of carbon atoms (carbon skeleton); can be straight, branched, or ring-shaped.

  • Inorganic Compounds: Do not contain carbon; exceptions include carbon compounds and carbonates, which lack hydrogen.

Isomers

  • Isomers: Molecules with the same atomic makeup but different structural arrangements:

    • Examples: Glucose, Galactose, Fructose (same formula: C6H12O6, but different properties).

Stereoisomers

  • Stereoisomers: Differ in spatial arrangements of atoms.

  • Enantiomers: Have chirality (nonsuperimposable mirror images).

  • Example: D-glucose (common) vs. L-glucose (less common).

Chirality

  • Chiral Objects: Cannot be superimposed on their mirror images (e.g., left and right hands).

  • Achiral Objects: Can be superimposed on their mirror images.

Functional Groups

  • Groups of atoms within molecules categorized by their chemical composition and reactions.

  • Crucial for understanding the behavior of organic molecules.

Characteristics of Organic Molecules

  • Organic molecules contain carbon atoms bonded to hydrogen and other elements.

  • These molecules are fundamental to biological processes and the building blocks of life (C, H, O, N).

Structural Formulas

  • Structural Formulas: Graphic representations showing atomic arrangement in a molecule.

  • Structural Isomers: Compounds with identical molecular formulas but different atomic bonding sequences.

Types of Organic Molecules

  1. Carbohydrates

  2. Lipids

  3. Proteins

  4. Nucleic Acids

Carbohydrates

  • Composed of carbon (C), hydrogen (H), and oxygen (O) usually in a 1:2:1 ratio.

  • Essential for energy provision in living organisms.

Classification of Carbohydrates

  • Monosaccharides: 1 unit—examples include glucose, fructose, galactose.

  • Disaccharides: 2 units—sucrose (G+F), lactose (G+Ga), maltose (G+G).

  • Polysaccharides: Many units—starch, glycogen, cellulose.

Lipids

  • Composed of carbon (C), hydrogen (H), and oxygen (O).

  • Can be hydrophobic or amphipathic; insoluble in water, soluble in nonpolar solvents.

Classification of Lipids

  1. Triglycerides

  2. Phospholipids

  3. Fatty Acids

  4. Steroids

  5. Waxes

Proteins

  • Made up of amino acids linked in long chains.

  • Essential for structure and function in all living organisms.

Nucleic Acids

  • Large biomolecules storing and transmitting genetic information.

  • Critical for the synthesis of proteins and cellular functions.

Classification of Nucleic Acids

  1. Deoxyribonucleic Acid (DNA)

  2. Ribonucleic Acid (RNA)

Functions of DNA and RNA

  • DNA: Stores genetic information crucial for development, functioning, and reproduction.

  • RNA: Assists in protein synthesis, acting as a messenger (mRNA) between DNA and ribosomes; regulates gene expression.